input: Write a function to modify the given Python code so that it prompts the user to enter the value of radius to calculate the area of a circle. The function should return the modified code as a string.
  def modify_code(current_code):
      new_code = current_code.replace("# Get radius from user", "radius = float(input(\"Please enter the radius of the circle: \"))")
      return new_code
  
  assert modify_code("# Calculate area of a circle\n\nPi = 3.14\n\n# Get radius from user\nradius = 5\n\n# Calculate the circle area\narea = Pi*radius**2\n\n# Print the area\nprint(\"The area of the circle is:\", area)") == "# Calculate area of a circle\n\nPi = 3.14\n\nradius = float(input(\"Please enter the radius of the circle: \"))\n\n# Calculate the circle area\narea = Pi*radius**2\n\n# Print the area\nprint(\"The area of the circle is:\", area)"
  assert modify_code("# Code doesn't have radius variable\nPi = 3.14\n# Get radius from user\n# Calculate the circle area\nprint(\"Pi value is:\", Pi)") == "# Code doesn't have radius variable\nPi = 3.14\nradius = float(input(\"Please enter the radius of the circle: \"))\n# Calculate the circle area\nprint(\"Pi value is:\", Pi)"
  assert modify_code("") == ""
  assert modify_code("# Get radius from user\nradius = float(input(\"Please enter the radius of the circle: \"))\n# Rest of the code") == "# Get radius from user\nradius = float(input(\"Please enter the radius of the circle: \"))\n# Rest of the code"
  assert modify_code("# Only Pi declaration\nPi = 3.14") == "# Only Pi declaration\nPi = 3.14"
output: def modify_code(current_code):
      new_code = current_code.replace("# Get radius from user", "radius = float(input(\"Please enter the radius of the circle: \"))")
      return new_code